I was finally able to get a picture of Fishie on his hammock. I took it with my phone so it's not the greatest quality.
I noticed that he likes it best when it's really close to the surface. Last time I changed his water I put it a little farther down into the water, and he didn't go on it as much. But today I changed his water and put it close to the surface and he rests on it a lot now.
Sometimes he rests sideways on the stem of it. haha